/**
* @Description:修改表单的子级搜索树组件
* @author NewLore1
* @Date 2020/12/01/10:51
* @LastEditors: 乔
* @LastEditTime: 2020/12/01/10:51
**/
<template>
  <el-select ref="select" :disabled="disabled" :value="valueTitle" :clearable="clearable" :placeholder="placeholder" @clear="clearHandle">
    <el-input v-model="filterText" class="selectInput" placeholder="检索关键字" />
    <!-- @change="item.change && item.change(editData[item.prop])"  props.value -->
    <el-option :value="valueTitle" :label="valueTitle" class="options">
      <el-tree id="tree-option" ref="selectTree" :accordion="accordion" :data="options" :props="props" :node-key="nodekeys" :default-expanded-keys="defaultExpandedKey" :filter-node-method="filterNode" @node-click="handleNodeClick" />
    </el-option>
  </el-select>
</template>

<script>
export default {
  name: 'ElTreeSelect',
  props: {
    /* 配置项 */
    props: {
      type: Object,
      default: () => {
        return {
          value: 'id', // ID字段名
          label: 'title', // 显示名称
          children: 'children' // 子级字段名
        };
      }
    },
    /* 选项列表数据(树形结构的对象数组) */
    options: {
      type: Array,
      default: () => {
        return [];
      }
    },
    /* 初始值 */
    value: {
      default: () => {
        return null;
      }
    },
    /* 可清空选项 */
    clearable: {
      type: Boolean,
      default: () => {
        return true;
      }
    },

    /* 自动收起 */
    accordion: {
      type: Boolean,
      default: () => {
        return false;
      }
    },
    placeholder: {
      type: String,
      default: () => {
        return '请选择';
      }
    },
    // 是否可编辑
    disabled: {
      type: Boolean,
      default: () => {
        return false;
      }
    },
    // 唯一识别值
    nodekey: {
      type: String,
      default: () => {
        return 'id';
      }
    }
  },
  data() {
    return {
      nodekeys: this.nodekey,
      filterText: '',
      valueId: this.value, // 初始值
      valueTitle: '',
      defaultExpandedKey: []
    };
  },
  watch: {
    value() {
      this.valueId = this.value;
      this.initHandle();
    },
    filterText(val) {
      this.$refs.selectTree.filter(val);
    }
  },
  mounted() {
    this.initHandle();
  },
  methods: {
    // 初始化值
    initHandle() {
      // console.log('初始化值nodekeys：', this.nodekeys);
      // console.log('初始化值valueId：', this.valueId);
      if (this.valueId) {
        var node = this.$refs.selectTree.getNode(this.valueId);
        if (node) {
          this.valueTitle = this.$refs.selectTree.getNode(
            this.valueId
          ).data[this.props.label]; // 初始化显示
          this.$refs.selectTree.setCurrentKey(this.valueId); // 设置默认选中
          this.defaultExpandedKey = [this.valueId]; // 设置默认展开
        }
      }
      this.initScroll();
    },
    // 初始化滚动条
    initScroll() {
      this.$nextTick(() => {
        const scrollWrap = document.querySelectorAll(
          '.el-scrollbar .el-select-dropdown__wrap'
        )[0];
        const scrollBar = document.querySelectorAll(
          '.el-scrollbar .el-scrollbar__bar'
        );
        scrollWrap.style.cssText =
                    'margin: 0px; max-height: none; overflow: hidden;';
        scrollBar.forEach(ele => (ele.style.width = 0));
      });
    },
    // 切换选项
    handleNodeClick(node) {
      // this.valueTitle = node[this.props.label];
      // this.valueId = node[this.props.value];
      // this.$emit('getValue', this.valueId);
      this.$emit('getValue', node); // 返回点击树所有值
      this.defaultExpandedKey = [];
      this.$refs.select.blur();
    },
    // 清除选中
    clearHandle() {
      this.valueTitle = '';
      this.valueId = null;
      this.defaultExpandedKey = [];
      this.clearSelected();
      this.$emit('getValue', null);
      this.$emit('clear', null);
    },
    /* 清空选中样式 */
    clearSelected() {
      const allNode = document.querySelectorAll(
        '#tree-option .el-tree-node'
      );
      allNode.forEach(element => element.classList.remove('is-current'));
    },
    filterNode(value, data) {
      if (!value) return true;
      return data.name.indexOf(value) !== -1;
    }
  }
};
</script>

<!-- 添加scoped属性，是为了让css只在该组件生效，避免样式污染 -->
<style scoped>
.el-scrollbar .el-scrollbar__view .el-select-dropdown__item {
  height: auto;
  max-height: 274px;
  padding: 0;
  overflow: hidden;
  overflow-y: auto;
}
.el-select-dropdown__item.selected {
  font-weight: normal;
}
ul li >>> .el-tree .el-tree-node__content {
  height: auto;
  padding: 0 20px;
}
.el-tree-node__label {
  font-weight: normal;
}
.el-tree >>> .is-current .el-tree-node__label {
  color: #409eff;
  font-weight: 700;
}
.el-tree >>> .is-current .el-tree-node__children .el-tree-node__label {
  color: #606266;
  font-weight: normal;
}
.selectInput {
  padding: 0 5px;
  box-sizing: border-box;
}
</style>

